Automatic Coiled Tubing Injector Chain Management System

ABSTRACT

The present application pertains to an injector chain control system for a coiled tubing unit. The system may comprise real time data received from sensors monitoring depth, pressure, force and other aspects of the well bore. The amount of hydraulic, electric, or pneumatic pressure allocated to the chain system may control both tension and traction system using the pressure as an indicator or trigger for the electronic feeding of information. A return feedback of the chain system may preset operating limits provided by well profile depths, pressures, temperatures, and/or composition of well contents in fluid, gaseous, and/or solid based. An injector chain system with or without a chain lubrication system may have a chain which is lubricated via an automated or manual system which can be triggered via a predetermined chain footage travel or timed interval, based on factors such a traction and/or tension pressure.

CROSS-REFERENCE TO ELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.63/158,946 filed on Mar. 10, 2021 which application is incorporatedherein by reference.

FIELD OF THE INVENTION

This invention relates to the application of delivering a securedbearing to prevent the shearing of a roller bearing pin from rotationalforce exerted through the axis by a secured shaft through a bearingblock attached to the rotational chain on equipment such as a coiltubing injector

BACKGROUND AND SUMMARY OF THE INVENTION

Coiled Tubing is a relatively new technology for the oil and gasindustry. It is used for interventions in oil and gas wells andproduction tubing. Previous to the introduction of Coil Tubing,Wirelining was used to complete similar operations. The most commonapplication is deliquification, and the dispersement of fluids to aspecific location in the well. Coiled Tubing has recently been used toassist in drilling operations.

The Coiled tubing is feed from a reel into the injector whicheffectively powers the tubing into the wellhead. The end of the coiledtubing string can be outfitted with numerous downhole tools includingdrill bits and other related drilling equipment. The “Gooseneck” is theangled piece on the injector which guides the tubing and allows abending of the coil string to allow it to go through the injector. It iswhat guides the tubing from the reel and directs the tubing from anupwards angle and turns it into a vertical down position into theinjector and through a Blow-out

Preventer (BOP) Stack into the Wellhead. The Injector and Gooseneck areconnected together and are suspended by a crane or similar liftedmethods for operations.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a coiled tubing path.

FIG. 2 shows the chains systems controlling the force on grippingblocks.

FIG. 3 shows a method for adjustment made by an operator of a coiledtubing unit.

FIG. 4 shows a tension system using hydraulic or electric power toactuate a cylinder (108) known as a tension cylinder.

DETAILED DESCRIPTION

This invention is directed towards the industry dependence on CoilTubing Injectors, specifically the control of the chain systems thatrotate under either hydraulic, electric power to provide a set ofrational gripper blocks to feed or pay tubing in or out of a well. Theinjector chain systems rotate around the chassis of the injector bymeans of a sprocket driven system that engages into the links of thechain forcing the chains to rotate via a track from the top to thebottom sprockets in and endless rotation. A representative coiled tubingpath is shown in FIG. 1.

As shown in FIG. 2 the chain systems further control the amount of forcedirected into the tubing gripping blocks during in-hole and out-holeoperations which is commonly known in the industry as Traction pressure.Hydraulic or electric forces push cylinders (103) outwards on to theinjector skates (102) which in turn push against the rollers in thechain forcing the chain (101) outwards into a more elliptical path andthus increasing the force on the gripper blocks (105) thereby increasinggrip on the tubing. Reversing the hydraulic or electrical forces willreduce the grip on the tubing.

As shown in FIG. 3 the method for this adjustment is made by theoperator of a coiled tubing unit, using the adjustment of a valve toillicit the prescribed response that is needed for operations.Typically, the increase in traction pressure results in greater grip forthe installed gripper blocks (105) on the tubing that traverses thru theinjector via the chain (101) and a reduction in traction pressureresults in lessoning the grip on the tubing that traverses thru theinjector via the chain (101).

The tension system further controls the amount of force directed ontothe chains (101) during in-hole and out-hole situations. The in-holedirection is the most critical direction due to the fact that the chainlinks can compress together or “bunch up”. This bunching up can causecatastrophic damage to the chain system. As shown in FIG. 4 the tensionsystem uses hydraulic or electric power to actuate a cylinder (108)known as a tension cylinder. The tension cylinder uses that force tomove the lower chain sprocket (107) away from the upper sprocket (106),to a load higher than the force generated on the chain in the upwarddirection thereby preventing a “bunching” of the chain during in-holemovements. The traditional method for this adjustment is made by theoperator of a coiled tubing unit, using the adjustment of a valve toillicit the prescribed response that is needed for operations.

There is no current system in use that would allow an operator toconsistently manage the chain system on a coiled tubing injector,running in both in-hole and out-hole operations. Adjustments are neededto the tension and traction pressures frequently and simultaneously whenthe tubing traverses to different depths in the wellbore. This can bedue to changes in fluid pressure of the well, changes in wellbore dragand the mass of the tubing downhole. Variations in these conditionsoccur and sometimes all variations of these conditions may be consideredto properly adjust the tension and traction pressure. Proper chaintension and traction are useful to decrease wear on consumable partssuch as chains (101) rollers (104), gripper blocks (105) and skates(102) while maintaining enough traction as to avoid slipping of thetubing through the injector. When not adjusted with the proper tensionand traction, these parts degrade considerably and can be a major causeof failure in injector heads. Avoiding down-time for maintenance isparamount in running an efficient coiled tubing job. Also, the operatorhas to divide their duties between spooling and unspooling a coil unit,observing key pressure indicating gauges, as well as mechanical gaugesduring operation. Removing the task of constantly adjusting the tensionand traction pressures will alleviate the operator from such tasks,freeing the operator's attention to wellbore safety. Control of thechain system also improves the lifecycle of the coiled tubing. This isseen in wear in the tubing, and undue markings from over-traction andunder-tension. The cost of the tubing is a company's greatestexpenditure for a consumable item. An improvement of 1015% of life ofthe tubing could be gained due to ridding of undue traction and tensionissues.

EMBODIMENTS

An injector chain control system for a coiled tubing unit; comprised of:

-   -   i) Real time data received from sensors monitoring depth,        pressure, force and other aspects of the well bore.    -   ii) The amount of hydraulic, electric, or pneumatic pressure        allocated to the chain system, to control both tension and        traction system using the pressure as an indicator or trigger        for the electronic feeding of information.    -   iii) Return feedback of the chain system to preset safe        operating limits provided by well profile depths, pressures,        temperatures, and composition of well contents; whether fluid,        gaseous, or solid based.    -   iv) An injector chain system with or without a chain lubrication        system whereas the chain is lubricated via an automated or        manual system which is triggered via a predetermined chain        footage travel or timed interval, based on factors such a        traction or tension pressure.

2. The chain control system of embodiment 1; whereas a pressure changeis triggered via an input based on the logic system composed of thecontents of embodiment 1.

3. The chain control system of embodiment 1; whereas traction andtension pressure is provided on data based off empirical data using aperformance chart of said injector adjusted by real time data from thewell, equipment degradation formulas or percentages, and/or coiledtubing attrition as it relates to previous jobs, and current exposure.

4. The chain control system of embodiment 1; whereas Loadcellinformation is provided in either hydraulic, electric, or pneumatic formto provide for logic.

5. The chain control system of embodiment 1; whereas a constant changein range of values based on immediate changes in traction pressuresustain a preset curve in change in tension pressure to maintain forces.

6. The chain control system of embodiment 1; whereas a sensing devicemeasures chain length as a wear function or chain length in anoverloaded condition and provides feedback for the logic device toindicate and notify of maximum chain load or chain wear life based uponexpected increase in length.

1. An injector chain control system for a coiled tubing unit; comprisedof: one or more sensors to monitor one or more of depth, pressure, andforce of the well bore and transmit real time data to a processor; achain system to control tension and an optional traction system, whereinthe amount of a hydraulic, an electric, or a pneumatic pressureallocated to the chain system uses force, pressure, or both; wherein thechain system is configured to employ operating limits based on one ormore of a well profile depth, a pressure, a temperature, and acomposition of well content; an optional chain lubrication systemwherein the chain lubrication system is configured to lubricate thechain system based on one or more of a predetermined chain footagetravel, a timed interval, a traction pressure, or a tension pressure. 2.The injector chain control system of claim 1 wherein a pressure changeis triggered based on one or more of the predetermined chain footagetravel, the timed interval, the traction pressure, or the tensionpressure.
 3. The injector chain control system of claim 1 wherein thetraction pressure, the tension pressure, or both is based on an adjustedinjector data.
 4. The injector chain control system of claim 3 whereinthe adjusted injector data is based on one more of real time data from awell, an equipment degradation formula, an equipment degradationpercentage, a coiled tubing attrition or a combination thereof
 5. Theinjector chain control system of claim 4 wherein the real time datacomprises injector data from previous jobs, from current exposure, or acombination thereof.
 6. The injector chain control system of claim 1wherein a loadcell data is provided to the processor in a formcomprising hydraulic data, electric data , pneumatic data, or acombination thereof.
 7. The injector chain control system of claim 1wherein the system is configured such that a force is maintained fromchanging a range of values based on immediate changes in tractionpressure to sustain a preset curve of change in tension pressure.
 8. Theinjector chain control system of claim 1 further wherein at least one ofthe one or more sensors is configured to measure a chain length as awear function, a chain length in an overloaded condition, or both, andwherein the system is configured to provide feedback for a logic deviceto indicate a maximum chain load, a maximum chain wear life, or bothbased upon an expected change in chain length.